Really like the office theme and the character designs are great! Using the cubicles as grind rails is very creative, though I feel they are a bit disconnected from the rest of the race. I found that I could either stick to speed boosting or using the cubicle, but couldn't switch between both without losing momentum.
The AI seems to find it hard to navigate certain parts of the track, which gave me a pretty big lead each race. I love the idea of different tracks that overlap with each other, I did sometimes lose track of where I was supposed to be going though, and just ended up going in circles without progressing.
Overall though I think this is a super fun idea for a racing game, great work! : )